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OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated.  相似文献   
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Release of ATP induced by hypertonic solutions in Xenopus oocytes   总被引:2,自引:0,他引:2  
ATP mediates intercellular communication. Mechanical stress and changes in cell volume induce ATP release from various cell types, both secretory and non-secretory. In the present study, we stressed Xenopus oocytes with a hypertonic solution enriched in mannitol (300 m m ). We measured simultaneously ATP release and ionic currents from a single oocyte. A decrease in cell volume, the activation of an inward current and ATP release were coincident. We found two components of ATP release: the first was associated with granule or vesicle exocytosis, because it was inhibited by tetanus neurotoxin, and the second was related to the inward current. A single exponential described the correlation between ATP release and the hypertonic-activated current. Gadolinium ions, which block mechanically activated ionic channels, inhibited the ATP release and the inward current but did not affect the decrease in volume. Oocytes expressing CFTR (cystic fibrosis transmembrane regulator) released ATP under hypertonic shock, but ATP release was significantly inhibited in the first component: that related to granule exocytosis. Since the ATP measured is the balance between ATP release and ATP degradation by ecto-enzymes, we measured the nucleoside triphosphate diphosphohydrolase (NTPDase) activity of the oocyte surface during osmotic stress, as the calcium-dependent hydrolysis of ATP, which was inhibited by more than 50 % in hypertonic conditions. The best-characterized membrane protein showing NTPDase activity is CD39. Oocytes injected with an antisense oligonucleotide complementary to CD39 mRNA released less ATP and showed a lower amplitude in the inward current than those oocytes injected with water.  相似文献   
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Infection of C57BL/6 (B6) mice with the Lyme disease spirochete Borrelia burgdorferi can result in development of arthritis and carditis. B. burgdorferi induces expression of beta2/CD18 integrins, adhesion molecules that mediate the firm adhesion of leukocytes to the endothelium necessary for cellular extravasation during inflammation. The important role of beta2/CD18 integrins during extravasation suggests that these molecules play a role in the development of Lyme arthritis and carditis. The dependency of these inflammatory processes on the beta2 integrins was investigated in CD18 hypomorph mice, which express low levels of CD18. The results indicate that CD18 deficiency did not abrogate development of Lyme arthritis or carditis. Moreover, it resulted in increased severity of Lyme carditis. B. burgdorferi-infected CD18 hypomorph mice showed an increased macrophage infiltration of the heart, while they produced lower levels of borreliacidal anti-B. burgdorferi antibodies compared to wild-type mice. In accordance with these results, we demonstrate that dendritic cells from CD18 hypomorph mice secrete higher levels of monocyte/macrophage chemoattractant protein 1 (MCP-1/CCL2) in response to B. burgdorferi. Similarly, we show by real-time PCR that B. burgdorferi-infected hearts from CD18 hypomorph mice express increased levels of MCP-1 RNA compared to wild-type mice. Overall, our results indicate that beta2 integrin deficiency does not abrogate B. burgdorferi-induced inflammation; rather, it results in increased recruitment of macrophages into the B. burgdorferi-infected heart, likely due to the increased expression of MCP-1 in this tissue. Thus, beta2 integrins may play a regulatory role in B. burgdorferi-induced inflammation beyond mediating adhesion of leukocytes to the endothelium.  相似文献   
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Despite growing evidence of the benefits of adequate intake of fruit and vegetables (F&V) and the recommendation to consume five servings daily, the adoption of these habits is poor among people with severe mental disorder (SMD). The main aim of the present study is to determine changes in the intake of F&V and motivation to do so among people with SMDs after participating in a food education programme. A community-based randomized controlled trial was conducted in Spain, with the intervention group (IG) participating in a food education programme based on the stages of change model to promote consumption of F&V and the control group (CG) receiving three informative sessions on basic healthy eating. The main outcomes were related to the intake of F&V and stages of change. Data collection was performed at baseline, post intervention, and 12-month follow-up. Seventy-four participants enrolled in the study and sixty completed the 12-month follow-up. An increase in motivation towards the intake of F&V was observed in the IG but not in the CG (McNemar’s test p = 0.016, p = 0.625). No significant difference was observed for the intake of fruit, vegetables, or F&V. Basing food education strategies on the stages of change model shows positive results, increasing the awareness and disposition of people with SMD towards the intake of F&V. More research is needed to identify the most appropriate eating intervention to increase the intake of F&V.  相似文献   
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IntroductionSeveral mechanisms play a role in the development of pneumonia after inhalation injury. Our aim was to analyze whether higher concentrations of inflammatory markers or of biomarkers of epithelial injury are associated with a higher incidence of pneumonia in patients with inhalation injury.Material and methodsSecondary analysis of a single-center prospective observational cohort pilot study, performed over a two-year period (2015–2017) at the Burns Unit of the Plastic and Reconstructive Surgery Department of Vall d’Hebron University Hospital. All patients aged 18 with suspected inhalation injury undergoing admission to the Burns Unit were included. Plasma biomarkers of the lung epithelium (RAGE and SP-D), inflammation markers (IL6, IL8), and IL33, as well as soluble suppression of tumorigenicity-2 (sST2) levels, were measured within the first 24 h of admission.ResultsTwenty-four patients with inhalation injury were included. Eight (33.3%) developed pneumonia after a median of 7 (4–8) days of hospital stay. Patients with pneumonia presented higher plasma concentrations of sST2 (2853 [2356–3351] ng/mL vs 1352 [865–1839] ng/mL; p < 0.001), IL33 (1.95 [1.31–2.59] pg/mL vs 1.26 [1.07–1.45] pg/mL; p = 0.002) and IL8 (325.7 [221.6–430.0] pg/mL vs 174.1 [95.2–253.0] pg/mL; p = 0.017) on day 1 of inclusion. Plasma sST2 concentration in the first 24 h demonstrated excellent diagnostic accuracy for predicting the occurrence of pneumonia in patients with smoke inhalation (AUROC 0.929 [95%CI 0.818–1.000]). A cutoff point of ≥2825 ng/mL for sST2 had a sensitivity of 75% and a specificity of 100%. The risk ratio of pneumonia in patients with sST2 ≥ 2825 ng/mL was 7.14 ([95% CI 1.56–32.61]; p = 0.016).ConclusionsPlasma sST2 in the first 24 h of admission predicts the occurrence of pneumonia in patients with inhalation injury.  相似文献   
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The esophageal cancer surgery is a complex procedure with elevated rates of both morbidity and mortality, which is why, in order to achieve adequate results, it should be performed in high volume centers, where complete multidisciplinary support is available and recent clinical guidelines are applied. We describe the initial experience and the technique of “tubeless” esophagectomy where esophageal resection and mediastinal lymphadenectomy are performed and no drains nor tubes of any kind are placed, with the aim to decrease the level of surgical aggression, enhance the postoperative comfort and accelerate the patient?s recovery.  相似文献   
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IntroductionAlthough several tools have been developed to assess general HRQoL in children, parental reports are required to supplement this information, especially in very young children. The parents version of the Kiddy-KINDL-R was developed to assess HRQoL in children aged 3 to 7 years through the reports of their parents or legal guardians.ObjectiveThe aim of this study was to validate the parents version of the Kiddy-KINDL-R questionnaire and assess its psychometric properties in a sample of Spanish preschool-aged children.MethodCross-sectional study in 283 parents or legal guardians of children aged 3 to 6 years that completed the Kiddy-KINDL-R questionnaire and an additional scale to assess anxiety problems. We performed confirmatory factor analysis to assess whether the original Kiddy-KINDL-R version fit the Spanish data; we assessed internal consistency by means of the ordinal alpha and the discriminant validity by means of the Preschool Anxiety Scale.ResultsAlthough the original six-factor model showed a good fit, we propose a model consisting of 22 items and the same 6 factors for the Spanish version. The reliability was excellent, and the internal consistency values were adequate. Our results showed significant negative correlations between the Kiddy-KINDL-R and the external anxiety measure, which was evidence of discriminant validity.ConclusionWe demonstrated that the Spanish version of the Kiddy-KINDL-R had good psychometric properties and that this questionnaire is an adequate assessment tool that could be useful in clinical practice.  相似文献   
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